/*
 * Copyright 2002-2019 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.transaction.interceptor;

import org.springframework.lang.Nullable;
import org.springframework.util.Assert;

import java.io.Serializable;
import java.lang.reflect.Method;

/**
 * Composite {@link TransactionAttributeSource} implementation that iterates
 * over a given array of {@link TransactionAttributeSource} instances.
 *
 * @author Juergen Hoeller
 * @since 2.0
 */
@SuppressWarnings("serial")
public class CompositeTransactionAttributeSource implements TransactionAttributeSource, Serializable {

    private final TransactionAttributeSource[] transactionAttributeSources;


    /**
     * Create a new CompositeTransactionAttributeSource for the given sources.
     *
     * @param transactionAttributeSources the TransactionAttributeSource instances to combine
     */
    public CompositeTransactionAttributeSource(TransactionAttributeSource... transactionAttributeSources) {
        Assert.notNull(transactionAttributeSources, "TransactionAttributeSource array must not be null");
        this.transactionAttributeSources = transactionAttributeSources;
    }

    /**
     * Return the TransactionAttributeSource instances that this
     * CompositeTransactionAttributeSource combines.
     */
    public final TransactionAttributeSource[] getTransactionAttributeSources() {
        return this.transactionAttributeSources;
    }


    @Override
    @Nullable
    public TransactionAttribute getTransactionAttribute(Method method, @Nullable Class<?> targetClass) {
        for (TransactionAttributeSource source : this.transactionAttributeSources) {
            TransactionAttribute attr = source.getTransactionAttribute(method, targetClass);
            if (attr != null) {
                return attr;
            }
        }
        return null;
    }

}
